This invention relates to a method and apparatus of separating and removing a dangerous substance such as white phosphorus included in exhaust gas generated in a semiconductor fabricating process by chemical vapor deposition or the like.
In general, a substance such as white phosphorus is included in exhaust gas generated in a semiconductor fabricating process by chemical vapor deposition. When the white phosphorus as a single substance is exposed to the air, it is combustible even at an ordinary temperature. Therefore, the work of removing the white phosphorus is usually dangerous and has invited many accidents.
To remove a dangerous substance such as white phosphorus in exhaust gas, there has been known a conventional method in which a filter is disposed at a suitable position of an inlet pipe through which the exhaust gas flows and the dangerous substance such as white phosphorus is removed in such a manner as to be separated from the exhaust gas through the filter.
Generally, the inlet pipe is small in diameter and therefore the exhaust gas flows rapidly through the inlet pipe. Accordingly, it is difficult to enhance the efficiency of separating white phosphorus or the like by means of the filter attached to the inlet pipe as in the above method. Further, even if the filter is arranged at plural positions of the inlet pipe, this only invites degradation of cost efficiency, and complete separation and removal of white phosphorus or the like is difficult and non-reliable.
The present invention has been made in view of the foregoing problems. The present invention has its object of overcoming the defects of the prior technique, that is, when the substance such as white phosphorus included in exhaust gas in a semiconductor fabricating process by chemical vapor deposition is separated and removed, enhancing the efficiency of separating the substance from the gas by a simple mechanism and securing safety in separation and removal of the substance.